This invention relates to novel benzopyran derivatives.
In copending, commonly assigned U.S. application Ser. No. 261,216, filed June 9, 1972 now U.S. Pat. No. 3,849,447, are described benzopyran derivatives of the general Formula I ##SPC2##
wherein R.sub.1, R.sub.2 and R.sub.3 are each lower alkyl; n is 1 or 2; &gt;A-B- is &gt;CH-CH.sub.2 - or &gt;C=CH-; X is free, esterified or etherified hydroxy; Y is H or X and Y collectively are =O.
Also disclosed therein is a process for the preparation of these benzopyran derivatives in which a compound of the general Formula II ##SPC3##
wherein R.sub.1, R.sub.2, R.sub.3, X, Y and n have the values given for Formula I, is cyclized in the presence of an acidic catalyst; and, optionally when X and Y are a keto group, the group is reduced to a hydroxy group; when a double bond is present in --A--B, the group is hydrogenated; when X is a free hydroxy group, the group is esterified or etherified and when X is an esterified hydroxy group, the group is hydrolyzed.
One drawback of the useful compounds described in the aforementioned copending application is the number of steps required to produce the starting materials therefor, which are described in more detail in the aforementioned U.S. Pat. No. 3,849,447. It is an object of the present invention to provide useful intermediates for the production of pharmacologically active steroids for which the starting materials are easily prepared.
Furthermore, the compounds of the aforementioned copending application are intermediates for the production of des-A-steroids and it is an object of the present invention to provide useful intermediates which can be converted to steroids per se.
The present invention relates to novel benzopyran derivatives which differ from the compounds of the prior-filed application by the type of R.sub.2 groups in the molecule.